package com.hmdp.utils;

import cn.hutool.core.io.resource.ClassPathResource;
import cn.hutool.core.lang.UUID;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.Resource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;

import java.util.Collections;
import java.util.concurrent.TimeUnit;

public class SimpleRedisLock implements Ilock{


    private StringRedisTemplate stringRedisTemplate;
    private static final DefaultRedisScript<Long> UNLOCK_SCRIPT;
        static {
            UNLOCK_SCRIPT = new DefaultRedisScript<>();
            UNLOCK_SCRIPT.setLocation((Resource) new ClassPathResource("unlock.lua"));
            UNLOCK_SCRIPT.setResultType(Long.class);
        }


    private String name;
    private static final String KEY_PREFIX = "lock:";
    private static final String ID_PREFIX = UUID.randomUUID().toString(true)+"-";
    public SimpleRedisLock(String name,StringRedisTemplate stringRedisTemplate) {
        this.name = name;
        this.stringRedisTemplate = stringRedisTemplate;

    }
    @Override
    public boolean tryLock(long timeoutSec) {
        //获取全局唯一ID，这里采用线程标识
        String threadId = ID_PREFIX+Thread.currentThread().getId();
        //获取锁
        Boolean success = stringRedisTemplate.opsForValue()
                .setIfAbsent(KEY_PREFIX+name, threadId+"",timeoutSec, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(success);
    }

    @Override
    public void unlock() {
        //调用Lua脚本
        stringRedisTemplate.execute(
                UNLOCK_SCRIPT,
                Collections.singletonList(KEY_PREFIX+name),
                ID_PREFIX+Thread.currentThread().getId()
        );


    }

    /*@Override
    public void unlock() {
        //获取线程标识：
        String threadId = ID_PREFIX+Thread.currentThread().getId();
        String lockId= stringRedisTemplate.opsForValue().get(KEY_PREFIX+name);
        //判断是否一致
        if(lockId.equals(threadId)){
            stringRedisTemplate.delete(KEY_PREFIX+name);
        }
        //释放锁

    }*/
}
